University of Missouri

Other

Zbylut J Twardowski

W Kirt Nichols

John C Van Stone

Karl D Nolph

Ramesh Khanna

Rodney S Kenley

A catheter for hemodialysis comprises a flexible catheter tube defining a plurality of separate lumens. The catheter defines an arc angle of generally U-shape in its natural, unstressed configuration. Thus, the catheter may be implanted with a distal catheter portion residing in a vein of the patient, the distal catheter portion being of substantially the shape of the vein in its natural, unstressed condition. Also, a proximal catheter portion resides in a surgically created tunnel extending from the vein and through the skin of the patient, this section of the catheter also being typically in its natural, unstressed condition. Thus blood may be removed from the vein through one lumen of the catheter, and blood may be returned to the vein through another lumen of the catheter, while the catheter is subject to long term indwelling in the body. Improved results are achieved because of the lack of mechanical stress in the shape of the catheter, which stress causes the catheter to press unduly against adjacent tissues.

Multiple lumen catheter for hemodialysis

The method of selecting and implanting a permanent venous catheter into a patient for use in chronic, extracorporeal blood treatment procedures. The method comprises determining the Body Surface Area of the patient. One then selects a permanent venous catheter having an actual length which is within 10% of a desired length as indicated in a Table found in this application for the Body Surface Area of the particular patient and a particular vein through which the catheter is to extend. Also, the internal diameter of the tubing is preferably adjusted in a manner correlating with the catheter length. Following catheter selection, the venous catheter is implanted in the venous system of the patient with the distal tip of the catheter being in or adjacent to the upper right atrium of the heart.

Patient-tailored, central-vein catheters

A central-vein cathether is locked by anticoagulant and bactericidal solutions separated by an air bubble. The anticoagulant is injected first, then the air bubble, and then the bactericidal solution, so that the anticoagulant is located close to the catheter tip in contact with the blood and the bacterial solution is located close to the catheter hub, where bacteria contamination is common. The air bubble prevents mixing of the solutions. A multi-chamber syringe facilitates sequential injection of the anticoagulant, air and bactericidal agent with only one connection, decreasing chances of contamination. The syringe includes internal and external coaxial barrels separated by seals, the external barrel having a discharge opening located off center in the barrel bottom, and the internal barrel having two or three chambers, each with an outlet opening. The internal barrel is rotatable relative to the external barrel to consecutively align the outlet openings with the discharge opening, allowing sequential injection of the contents. The syringe may also be used for aspiration of the locking fluid from the catheter with only one connection.

Method and apparatus for locking of central-vein catheters

A hemodialyzer apparatus comprises a reusable dialyzer membrane as well as reusable blood flow path and dialysis flow path units. The apparatus automatically primes itself and makes dialysis solution from dry chemicals, concentrates, and fresh water which is provided to the apparatus. Also, after use, the apparatus automatically prepares cleaning and rinsing solution for the cleaning and rinsing of the dialyzer membrane as well as the dialyzate and blood flow path means, to provide a system which is so simplified in terms of automatic operation that it may be usable for daily dialysis at home.

Method of preparing a batch of dialysis solution

A method for flushing and filling of an extracorporeal blood circulation system of a dialysis machine is disclosed. The machine has a dialyzer, a separate dialysis liquid circuit flowing through a dialysate side of the dialyzer with the extracorporeal blood circulation system flowing through a blood side of the dialyzer for removal of impurities from the blood and the dialysate and blood sides of the dialyzer separated by a hemodialyzer membrane. The method comprises the steps of transporting dialysis liquid from the dialysis liquid circuit in the dialysate side of the dialyzer through the hemodialyzer membrane into the blood side of the dialyzer and the extracorporeal blood circulation system to flush and fill the system and conducting a dialysis treatment.

Method for flushing and filling of an extracorporeal blood circulation

Blood is circulated through a multiple lumen catheter which connects between a vein of a patient and the blood treatment device. The catheter and the lumens thereof each define distal ends which are positioned within the vein. By this invention, one withdraws blood from the vein through one of the lumens at a flow rate of at least about 200 ml./min. while also inserting blood into the vein through another of said lumens at a similar flow rate. The distal ends of the lumens are longitudinally spaced from each other by no more than about 5 mm. It has been found that the following advantages can be achieved by this method: less clot formation coupled with low direct blood recirculation and longer catheter survival. Also, the catheter of this invention works well in either direction of blood flow through the respective lumens.

Clot resistant multiple lumen catheter

Artificial kidney for frequent (daily) hemodialysis

Blood is circulated through a multiple lumen catheter which connects between a vein of a patient and the blood treatment device. The catheter and the lumens thereof each define distal ends which are positioned within the vein. By this invention, one withdraws blood from the vein through one of the lumens at a flow rate of at least about 200 ml./min. while also inserting blood into the vein through another of said lumens at a similar flow rate. The distal ends of the lumens are longitudinally spaced from each other by no more than about 5 mm. It have been found that the following advantages can be achieved by this method: less clot formation coupled with low direct blood recirculation and longer catheter survival. Also, the catheter works well in either direction of blood flow through the respective lumens.

Clot resistant multiple lumen catheter and method

A catheter for hemodialysis comprises a flexible catheter tube defining a plurality of separate lumens. The catheter defines an arc angle of generally U-shape in its natural, unstressed configuration. Thus, the catheter may be implanted with a distal catheter portion residing in a vein of the patient, the distal catheter portion being of substantially the shape of the vein in its natural, unstressed condition. Also, a proximal catheter portion resides in a surgically created tunnel extending from the vein and through the skin of the patient, this section of the Catheter also being typically in its natural, unstressed condition. Thus blood may be removed from the vein through one lumen of the catheter, and blood may be returned to the vein through another lumen of the catheter, while the catheter is subject to long term indwelling in the body. Improved results are achieved because of the lack of mechanical stress in the shape of the catheter, which stress causes the catheter to press unduly against adjacent tissues.

Artificial kidney for frequent (daily) Hemodialysis

A multiple lumen, intravenous catheter for hemodialysis or the like defines a distal end portion in which at least a pair of the catheter lumens each communicates with the exterior through aperture means. By this invention the aperture means of one of the lumens defines a first port at essentially the distal catheter end, and the aperture means of the other of the lumens defines a second port spaced proximally along the catheter from the distal end and first port. The second port is positioned to face radially inwardly to at least a slight degree to avoid engagement of the wall of the blood vessel that the catheter occupies. Additionally, the tip of the catheter distal of the second port is preferably of substantially helically shape, being sized to assist in keeping the second port away from the blood vessel wall. As another feature, the catheter may be angled in its as-manufactured, unstressed condition to avoid pressing by elastic memory against internal blood vessel walls. Also, the catheter may define an inflatable balloon positioned between the first and second ports as a means for spacing particularly the second port away from blood vessel walls.

A peritoneal dialysis catheter comprises a distal tubular section and a proximal tubular section, connected together by a nonintegral tubular connector so that the respective sections are connected together in sealed flow relation. Such a catheter may be surgically implanted in the peritoneal cavity, extending to the chest of the patient with an end thereof protruding from the chest. The respective ends of the catheter section may be connected to each other through the tubular connector as the tubular sections are surgically implanted, and typically after such implantation is substantially complete.

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Columbia, MO, United States of America

Zbylut J Twardowski